Replaceable transom chine, etc.



May 22, 1962 R. c. BARTLEY 3,035,284

REPLACEABLE TRANsoM CHINE, ETC.

Filed Aug. 14, 1961 IN V EN TOR.

BY MKM United .States arent 3,035,284 REPLACEABLE TRANSOM CHINE, ETC. Ronald Clark Bartley, 3821 S. 1215 E., Salt Lake City, Utah Filed Allg. 14, 1961, Sel'. No. 131,277 1 Claim. (Cl. 96)

My invention relates to a replaceable transom chine to be used at the base of the transom of power boat hulls designed to plane on the surface of the water.

A primary object of this invention is to increase the speed and/or eiciency of a planing hull by providing and maintaining by replacement an exceptionally sharp transom chine, thereby reducing the amount of drag or friction caused by the displaced water.

Another important object of this invention is to oifer a practical and easy means of compensating or correcting for an undesirable shape permanently fixed in the bottom of a planing hull.

A further important object of this invention is that optimum performance and eiiiciency of a planing hull can be obtained under different conditions of weight distribution by selecting the correct transom chine insert.

Another object of this invention is that costly repair of a typical transom chine in common use can be greatly reduced by virtue of its simple and inexpensive replacement.

Referring to the drawings:

FIGURE 1 is an exploded fragmentary cross-sectional view of this invention and its position at the base of the transom.

FIGURE 2 is a three dimensional cross-sectional view of the same to illustrate several useful insert shapes.

yFIGURE 3 is a side cross-sectional view of the same showing several insert shapes of a ditferent type.

FIGURE 4 is a side view of a three-point hull illustrating use of this invention on hulls of this type.

FIGURE 5 is a three dimensional stern view of same.

FIGURE 6 is a conventional flat-bottomed hull illustrating use of this invention on hulls of this type.

FIGURE 7 is a three dimensional stern view of same.

IFIGURE 8 is a three dimensional stern view of a V-bottomed hull showing placement of this invention on hulls of this type.

Referring to the drawings in detail, this invention consists of a channel-like holder 16 constructed as an individual unit independent of the boat or as a channel-like slot incorporated in said boat at the transom chine during or after construction, said holder 16 to extend the width of the transom chine and with a longitudinal internal ridge with a shape approximately as shown in FIGURE l; one or more longitudinally grooved inserts which will fit into and completely fill said holder .16 and which can be one of several hydrodynamically determined shapes, with said insert 15 firmly held in place while in operation by one or more fiat head screws 17. The relationships between this invention and various parts commonly used in boat construction are fragmentarily shown in FIGURE 1 and are a reinforcing transom knee 18, transom 19 and bottom 20.

This invention is to be incorporated into the base of a power boat transom as shown in FIGURES 1, 2 and 3 and in such a manner as to enable the leading edge of the holder 16 to be flush with the bottom of the boat 20 and the trailing edge of the insert 15 to be the transom chine.

If constructed independently, the holder 16 is to be made of a strong, non-corrosive material, preferably a metal, and designed so that a longitudinal ridge on the inner surface of the holder 16 will iit into a corresponding longitudinal groove in said insert 15 and thereby be firmly held and impossible for said insert 15 to move except in a direction parallel to holder 16. One or more at head screws are to be used to secure the insert 15 in place and prevent it from sliding out in a direction parallel to the holder. The inserts '15 are to be made of a tough, noncorrosive material, preferably a plastic or metal. If the inserts 15, holder 16 and at head screws 17 are made of metal, they must be all of the same composition to prevent galvanic action.

The trailing edge shape for the insert 15 most useful for general operation is a square degree) angle at the chine as shown in FIGURE l, since this will give the best overall performance for a Well-designed planing hull and will have the greatest resistance to becoming rounded through general use.

For a planing hull with a slightly convex bottom which commonly results from insufiicient support during storage or transport or from inadequate construction, an insert 15 as shown in FIGURE 2 which thickens aft to form a Wedge may improve the performance of specific hulls by increasing the lift at the stern through the use of said wedge-shaped insert 15. In addition, this wedge-shaped insert 15 may be used to maintain the most optimum operating attitude or trim of a speciiic hull when improper weight distribution in the boat is unavoidable.

For hulls designed specifically for speed such as the three-point hulls shown in FIGURES 4 and 5, an insert 15 may be advantageously used with an acute chine angle (less than 90 degrees) by further reducing drag of dis placed water and performance will also be improved for certain hulls by using an insert 15 with a trailing edge which is extended aft beyond the normal transom chine as shown in FIGURE 3 by providing a larger planing surface, thereby causing the boat to ride higher in the water and consequently with less drag.

FIGURES 6 and 7 show the placement and use of this invention on a conventional cruiser with a flat-bottomed hull.

This invention may also be readily adaptable on a V-bottomed or semi V-bottomed hull as shown in FIG- UR'E 8 by using two separate inserts 15 which slide into their respective holders 16 from opposite sides.

It will be understood that the shapes and dimensions shown in these drawings are given merely as an example suitable for a typical application.

I claim:

In a power boat of planing hull design, a replaceable transom chine comprising a channel-like holder constructed as a separate unit or as a channel-like slot incorporated in said boat with an internal longitudinal ridge; replaceable longitudinally-grooved inserts so designed. as to fit firmly inside said holder and with various hydrodynamically designed shapes and one or more at head screws to hold said insert rmly in place While in operation.

UNITED STATES PATENTS References Cited in the iile of this patent 2,031,428 Ragsdale Feb. 18, 1936 FOREIGN PATENTS 985,174 lFrance Mar. 7, 1951 

